World-renowned musician Richard Nunns has made a career out of researching, playing and teaching taonga puoro, the once-lost Maori traditional instruments that he helped revive. Seven years ago, he was struck with Parkinson's. He talks to Naomi Arnold about his life with the condition - and its remarkable effect on his music.

Was it the top-dressing planes floating a poisonous mist over the tiny cottage that Richard and Rachel Nunns shared as newlyweds? Was it a food preservative, an everyday cleaning product, or just a quirk in his genes? What about the chemically-saturated earth now under their feet in the former tomato-growing area of The Wood?

"Who knows?" Richard Nunns says. Why he developed the condition is one of the many missing parts of his Parkinson's puzzle. A bear of a man, he once swam competitively and ran in marathons and multisport events. Now he finds it difficult to walk to the supermarket.

The problems started very small, as these things do, with a slight cramping of the first joint of a finger. It wasn't until about 2005, when out walking on Walter's Bluff with his daughter Lucy, that things came to a head. With her nurse's training, she spotted that his right arm wasn't swinging naturally as he walked, and hauled him off to Nelson Hospital, with the diagnosis coming back after a month.

Problems with balance, tremors and stiffness in his limbs followed over the years, meaning he cannot traverse those steep paths any more.

"Now I'm reduced to shuffling around," he says, though not as gloomily as he could.

They recently moved from their Maitai home of 30 years to flatter ground in The Wood, and he has had to ban himself from driving as he cannot trust his body to do his bidding. He has trouble walking over the flat tiles of their courtyard without catching his feet, and keeps a walking stick propped in the hallway.

He's considering a mobility scooter because the walk from home to Fresh Choice is difficult to manage. He cannot eat without spilling food. Salads? Forget it. He cannot tie his shoelaces, fasten buttons, read easily, or write by hand. He surrenders to being patronised by flight attendants who call him "dear".

The drugs give him dreams "way beyond nightmares" in which he fights to the death, smashing lamps and punching holes in walls and doors. The sleeping horrors are so powerful that once, while dreaming about shaking hands with a woman who wanted to say goodbye, he awoke with two bruised and fractured fingers. He'd crushed them in his sleep; the dream woman wouldn't let go. "There's no getting out," he says, in the voice that Parkinson's has roughened to a low growl. He is just 66.

He has given up caring about most of the affronts. "In a lot of cases you just have to dispense with dignity,” he says. “What does it matter, for God's sake?"

And he is just one of thousands. Parkinson's, the degenerative neurological condition, affects about one in 500 New Zealanders. But the tremors seem a particularly cruel irony for a man who has spent his life creating delicate sounds from jazz flutes and hand-carved traditional Maori instruments.

But remarkably, despite the spilling, the tripping, the shaking, his brain has mostly left his music alone. He still plays the stirring, haunting strains of the ancient sounds he helped revive.

Richard Nunns is the globe's foremost authority on Maori traditional music and taonga puoro, hotly sought-after for his mastery of the ancient flutes, whistles and other instruments that were once lost to the modern world.

He was introduced to nga taonga puoro in his early teens in the 1960s, and read an article about items held in the Auckland Museum that were presumed to be musical instruments - but nobody knew enough about them to confirm it. Moving to Nelson in the early 1970s he and carver Brian Flintoff met and began researching the instruments. They spent years deepening their knowledge with composer, singer, university lecturer, poet and author Hirini Melbourne, who died in 2003. It took the skills of all three to bring the music back as Maori music revival group Te Haumanu.

It would seem a condition involving shaking hands would see the delicate beauty of taonga puoro fade away. And yet, despite his Parkinson's, Nunns' contributions have only becoming more prolific. He stayed off drugs for as long as he could, though now swallows a palmful of pills every day. But when he holds an instrument and places it to his lips, his hands are mostly still. He can summon forth the music faultlessly; and cannot explain why.

"I have no idea," he says. "I dare say it'll be ultimately unravelled like everything else in the world, but [it's] the saving grace for me at the moment. The brain is pretty mysterious. I can barely eat my food sometimes. It's quite a spectacle; food goes everywhere. But I can perform to 10,000 on the Thames [during the Olympics] perfectly. I'm playing as well as I've ever played."

The disease is like someone sitting on his shoulders, telling him to give up, to slow down. But he believes the single thing keeping him alive is doing what he loves, and performing on an international platform is keeping him on a plateau of wellness.

"I can sit in the studio and shiver and flake and carry on, and yet I'm opening a film at the Suter no trouble at all. Yeah, it's weird."

He has had to make adjustments; he tires easily, so he plays sitting down, and everywhere he goes he has to explain that ancient Maori wouldn't have played in quite the same way.

His new life is not without its lighter moments. He demonstrated the instruments to students at one local high school, and then they made small flutes from bamboo. After she'd finished, one 14-year-old girl approached him, ready to show off her skills. She picked up the flute, placed it against her lips - and started shaking it slightly, as he had done. "She was completely serious. It made me very careful," Nunns says. "I realised that in 10 minutes you could change the world."

Scientists have proven music does indeed help release dopamine in the brain, the lack of which causes the problems of Parkinson's. Doctors have, in fact, prescribed music to treat it, as well as other problems like stroke, Alzheimer's, ADHD, autism and dementia.

University of Otago Brain Health Research Centre neuroscientist and Parkinson's researcher Louise Parr-Brownlie says anything that keeps a Parkinson's patient active is "a really good thing". The tremors occur at rest, so as soon as sufferers focus on performing a task, they can be overridden.

"There are many pathways in the brain that are important for movement, and it's one particular pathway that's affected in Parkinson's disease," she says. "That will be affecting many aspects of his movement, but because he's a very highly skilled musician he is also recruiting other motor pathways, probably involving the cerebellum, and that will be how he's able to still continue playing his music but is still a Parkinson's patient."

Since his diagnosis Nunns had perhaps his most accomplished years yet, with accolades stacking up. They include a QSM, an honorary doctorate from Victoria University, an arts laureate, and entry into the New Zealand Music Hall of Fame. As well, the sounds of taonga puoro have seeped into New Zealand's musical canon. It's music that belongs to the country, that could have come from nowhere else in the world.

A few years ago, when he recorded He Ara Puoro, a 34-part series for Concert Radio at Wellington's Karori Wildlife Sanctuary, native birds flew down to investigate - a kea one day, a stitchbird the next.

Those sounds are in demand in every musical genre, from chamber music to hip-hop. "I say yes to everything.”

He's now become a mentor for

young Maori singers such as Ariana Tikao, and the musical elasticity developed through playing 40 years of jazz has resulted in collaborations with the New Zealand String Quartet, Jonathan Lemalu, Tiki Taane, Madeleine Pierard, Whirimako Black, Dudley Benson, Salmonella Dub, King Kapisi, Pitch Black's Paddy Free, and even Icelandic enigma Bjork.

King Kapisi's brand of Overstayer T-shirts have become a sort of trademark for Nunns. He wears them everywhere, as he can pull them over his head without bothering with buttons.

Yet the process hasn't been easy for his family and friends to watch.

His wife, who writes under the name Rachel Bush, says the disease has changed their life completely. They used to enjoy walking together, on the paths around the Maitai or at Rabbit Island. The time after diagnosis was strange, she says.

There was no impetus to act, no treatment such as radiation or chemotherapy to rush into - just a new awareness, a slight sense of dread, to sit with them in the days and weeks that followed.

"It's quite hard in many ways,” she says. “The things you enjoy doing together like walking - that was something we did for years and years. And you know it's not going to get better."

Friend and musical colleague, Monaco carver Brian Flintoff, says his biggest emotion is “complete amazement” at how Nunns manages to carry on with such limited mobility. They've had to adapt some of his carved instruments so they're easier to play, but Nunns' schedule is still “unbelievable”, Flintoff says. “It seems to have almost picked up, in the number of trips that he's having to make overseas.”

Originally both teachers, the pair met at a hui called to discuss creating the whare at Whakatu in the late 1970s, and their long careers in Maori music continue today with workshops for younger people eager to learn taonga puoro for themselves. Flintoff says Nunns' Parkinson's has had an unexpected effect in that it's hurried up the students' learning.

"It gives people confidence - with his shaking he can do it, so they better step up. It's made people think they better be ready to take over.

"Now the revival movement continues because [the people] are doing it in their own way, and because they've got the expertise in making instruments and playing instruments the younger ones don't need to call on us so often. It's a new generation and we'd be failures if we hadn't promoted that. It was always a strong theme."

Flintoff recalls the years before Melbourne died of lung cancer, and although Parkinson's doesn't kill you - you die with it, rather than of it - he sees a similar theme in Nunns' attitude to music.

"It's a reason to get out of bed in the morning, to carry on. You don't give up, which is the same as our friend Hirini when he was diagnosed with cancer and was quite sick. He continued, right to the last minute with his last recording.

"They carried him out of the recording studio and into life support on the hospital, which he didn't go away from. Even the really traumatic times, they brought in the first cut of the CD and he was saying ‘Do this, do that'.

"Having something that you're doing that you can continue to make a focus of your life; you realise how lucky you are to have something that's important to you."

Nunns says the condition makes him focus on the important things, stripping out the extraneous - such as their television which they did not replace after the old one blew up. It's a concept that's moved into his work, too. He stopped reading music years ago, and now finds he plays fewer notes, adding more gravitas to the notes he does play and avoiding the indulgence of technically showing off. "It fits with re-examining what you're doing."

Te More, a project with Whirimako Black, who he met at the tangi for Melbourne, her uncle, is an album chilling in its minimalism. Nunns explains in the liner notes that it offered an opportunity to strip right back, creating a conversation between voice and taonga puoro. It's one of 22 albums this year, and several films. A book, to be published by Craig Potton and co-written with the late Allan Thomas, is in the wings.

"I like to think I can still do the business," he says.

He's travelled to about 20 countries in the past couple of years.

"I'm very flattered by the attention of people from all around the world. It sounds a bit grandiose, but often they will come to me and say ‘Can we try something?' ”

He says his "plateau of wellness" will degrade, and when it does he is worried his music might get worse without him noticing. He's told a friend: "For Chrissakes, tell me to stop when it's not happening.”

But it hasn't come up.

"I have been given this tiny gift of working with instruments that have nothing to do with orthodox music in the Western sense. Musically, there's so many things I can't do, but I've found this niche.”

When he found out he had Parkinson's, he thought "That's not fair".

“The moment, the very moment you've arrived at a level of performance that is of international quality, for want of a better word, you go and get sick,” he says. But as it turned out, the thoughts of unfairness were “pointless” emotions.

His music has barely suffered; in fact, it's the easiest thing in his life.